Quote from: Lars-J on 06/11/2015 11:55 pmQuote from: rayleighscatter on 06/01/2015 04:46 pmFirst two flight engines complete. First engine has gone through 7 test firings in 2 months completing acceptance testing, second engine starts testing this week.Pad work expected to be complete in SeptemberFirst stage modifications on existing cores on scheduleMarch 2016 expected date of first launch with one month existing schedule margin.Are they going to test fire these engines themselves at Stennis? Or simply accept then as-is?Energomash is doing the acceptance test firings, after which the engines will be shipped to the States and integrated with the vehicle.
Quote from: rayleighscatter on 06/01/2015 04:46 pmFirst two flight engines complete. First engine has gone through 7 test firings in 2 months completing acceptance testing, second engine starts testing this week.Pad work expected to be complete in SeptemberFirst stage modifications on existing cores on scheduleMarch 2016 expected date of first launch with one month existing schedule margin.Are they going to test fire these engines themselves at Stennis? Or simply accept then as-is?
First two flight engines complete. First engine has gone through 7 test firings in 2 months completing acceptance testing, second engine starts testing this week.Pad work expected to be complete in SeptemberFirst stage modifications on existing cores on scheduleMarch 2016 expected date of first launch with one month existing schedule margin.
Copy the nk-33 engine, and use the copy on several flights of the Antares rocket, before using it on an 'Atlas VI' rocket. The nk-33's predecessor, the nk-15, recieved lots of development for the N-1 moon rocket. The Antares supply missions to the ISS are a good way to flight test a rocket engine. If an engine fails, the cost of failure is low. The Antares launch pad is cheap to fix. The first stage tanks are cheap. The ATK solid upper stage is cheap. The supplies to the ISS are cheap.The uprated nk-33s, will produce ~333 tons of thrust sl, versus the ~400 tons of thrust of the rd-180. It will also have a lower isp, 297 nk-33, vs 311 rd-180. But, solid rocket boosters can compensate for lower performance.I argue that the nk-33 engine is easier to build, for a nation inexperienced in oxygen rich hydrocarbon staged combustion engines, than the rd-180. The upgraded nk-33 has a lower chamber pressure around ~155 bar, versus the ~250 bar of the rd-180. The rd-170 also took a decade for the Soviet Union to develop, in spite of already having the experience of developing the nk-33. Aerojet has looked at the nk-33 for over a decade, with 4 successful flights, and analyzing the Antares failure will reveal even more about the nk-33. The United States still has over 20 nk-33s in stock. Even more engines remain in Russian hands. Gradually, different nk-33 parts could be developed, and flown, until an engine made entirely from American parts is flown. Saddam followed that strategy in copying the s2.720 engine.I don't know how much of a copy the AR-1 is of the NK-33.
Copy the nk-33 engine ...
I think any proposal to take an NK engine and run it closer to the margins is going to be a tough sell these days.OrbATK maintains that the NK designs have been shown to be fundamentally unreliable.Don't know exactly how AR-1 is setup, but I think it's actually closer to the RD series than the NK engines.Interesting point about chamber pressures though, I don't know what the targets are for AR-1, BE-4, etc.
Quote from: arachnitect on 06/25/2015 07:01 pmI think any proposal to take an NK engine and run it closer to the margins is going to be a tough sell these days.OrbATK maintains that the NK designs have been shown to be fundamentally unreliable.Don't know exactly how AR-1 is setup, but I think it's actually closer to the RD series than the NK engines.Interesting point about chamber pressures though, I don't know what the targets are for AR-1, BE-4, etc.I figure nk-33 copy would gradually have its chamber pressure, and thrust, increased, like the Merlin 1 engine has been.
Some stories have mentioned cracking from age. In fact: http://www.nasaspaceflight.com/2014/05/antares-aj-26-engine-fails-stennis-testing/I figured it was age of the engines, and maybe Soviet workmanship...
I wonder if the N-1 rocket could have become a reliable rocket if the Soviet Union had put in more time and money.
As both a launch vehicle builder and a propulsion system supplier, Orbital ATK is uniquely positioned to support the Air Force RPS Prototype Program. Orbital ATK has proposed both solid and liquid propulsion developments that will support a new all-American launch vehicle family that meets all the specified national security launch needs. Our new systems will be developed in a public/private partnership with significant private investment supplementing government funding. We are confident that our alternatives will be ready to support first flights by early 2019. For our vehicles and propulsion systems, we will combine advanced solid rocket motor and liquid engine technologies to create a modular family of highly affordable and commercially competitive launch vehicles. Beyond their contribution to assured and affordable access to space, these new systems will also strengthen our country's technology base and increase its industrial utilization to benefit the U.S. Navy and Air Force's strategic missile, MDA's missile defense and NASA's human space flight programs as well.
While the United States is the world's undisputed leader in development and production of solid rocket motors, the same cannot be said for our current position related to large liquid rocket engines. Fortunately, this deficiency is now being addressed by the progress being made by Blue Origin in its BE-3 and BE-4 liquid hydrogen and methane engine programs which are being developed with private investment. Based on the progress thus far, the BE-3/BE-4 engines have the potential to advance United States liquid rocket engines far ahead of what is currently being produced overseas. And like the solid propulsion technology we are developing internally, we believe the BE engines can be available for operational use by 2019 and will be offered at commercially attractive prices.
[recommendation 3] Encourage the Air Force to expand its EELV Phase 2 program to include consideration of medium-lift vehicles in addition to intermediate- and heavy-lift launchers.
From the 6/26/15 HASC hearing: http://docs.house.gov/meetings/AS/AS29/20150626/103668/HHRG-114-AS29-Wstate-CulbertsonF-20150626.pdfQuote from: Frank CulbertsonAs both a launch vehicle builder and a propulsion system supplier, Orbital ATK is uniquely positioned to support the Air Force RPS Prototype Program. Orbital ATK has proposed both solid and liquid propulsion developments that will support a new all-American launch vehicle family that meets all the specified national security launch needs. Our new systems will be developed in a public/private partnership with significant private investment supplementing government funding. We are confident that our alternatives will be ready to support first flights by early 2019. For our vehicles and propulsion systems, we will combine advanced solid rocket motor and liquid engine technologies to create a modular family of highly affordable and commercially competitive launch vehicles. Beyond their contribution to assured and affordable access to space, these new systems will also strengthen our country's technology base and increase its industrial utilization to benefit the U.S. Navy and Air Force's strategic missile, MDA's missile defense and NASA's human space flight programs as well.Quote While the United States is the world's undisputed leader in development and production of solid rocket motors, the same cannot be said for our current position related to large liquid rocket engines. Fortunately, this deficiency is now being addressed by the progress being made by Blue Origin in its BE-3 and BE-4 liquid hydrogen and methane engine programs which are being developed with private investment. Based on the progress thus far, the BE-3/BE-4 engines have the potential to advance United States liquid rocket engines far ahead of what is currently being produced overseas. And like the solid propulsion technology we are developing internally, we believe the BE engines can be available for operational use by 2019 and will be offered at commercially attractive prices. Quote [recommendation 3] Encourage the Air Force to expand its EELV Phase 2 program to include consideration of medium-lift vehicles in addition to intermediate- and heavy-lift launchers. So... a modular vehicle family including advanced solid motors and some kind of liquid engine technology. Starts at medium-class vehicle. Hints of Blue Origin Engines being involved? Intended for DOD operations, so no engines designed or built in Russia...Any guesses? Something that looks like Titan? Or the abandoned Ariane 6 PPH proposals? Return of "the stick"?
I'm picking solid booster and BE3 upper stage. The upper stage may happen sooner as RD181 Antares and BE3 upper would allow Orbital to go after commercial and NASA GEO missions. A RD181 Antares with BE3 upper would be ideal for SNC crewed DC.
Quote from: TrevorMonty on 06/28/2015 06:33 amI'm picking solid booster and BE3 upper stage. The upper stage may happen sooner as RD181 Antares and BE3 upper would allow Orbital to go after commercial and NASA GEO missions. A RD181 Antares with BE3 upper would be ideal for SNC crewed DC. I figure you'd need two solid stages to do a drop in replacement of the kerolox stage.Probably a 3 segment first stage and a 1 or 1.5 segment second stage.But the problem with that is handling of the heavy segments at Wallops not a show stopper but would be a significant added cost.But the ATK part probably does want to market the solids they're building for SLS in other markets since the R&D is mostly paid for and it means one less thing to buy from an outside contractor.
If you are thinking STS SRBs, than the only current pad capable of handling it would be LC-39B plus you will need a new MLP.